containerBuilder property
final
A function to build the container holding the overview map.
If not provided, the overview map will be 150x100 pixels with a 1 pixel
black border. Provide a function to return a customized container, such as
having the desired size, border, opacity, etc. The returned Widget must
include the provided child, which will be the overview map itself.
Implementation
final Widget Function(BuildContext context, Widget child)? containerBuilder;